Retinal signs and risk of incident dementia in the Atherosclerosis Risk in Communities study

Abstract

Introduction: The easily-imaged retinal microvasculature may reflect the brain microvasculature and therefore be related to dementia. Methods: In a population-based study of 12,482 adults aged 50-73 years (22% African American), we estimated the relationship of retinal characteristics from fundus photography (1993-1995) with incident all-cause dementia (1993-1995 to 2011-2013) and with etiologic subtype of dementia/mild cognitive impairment (2011-13). Results: A total of 1259 (10%) participants developed dementia over a mean 15.6 years. Moderate/severe (vs. no) retinopathy (hazard ratio [HR], 1.86; 95% confidence interval [CI]: 1.36–2.55) and central retinal arteriolar equivalent (narrowest quartile vs. widest three quartiles; HR, 1.26; 95% CI: 1.09–1.45) were associated with all-cause dementia. Results were qualitatively stronger (but not statistically significantly different) in participants with diabetes. Retinopathy was associated with a joint outcome of cerebrovascular-related, but not Alzheimer's disease–related, dementia/mild cognitive impairment (HR, 2.29; 95% CI: 1.24–4.23). Discussion: Exploration of measures in the eye may provide surrogate indices of microvascular lesions relevant to dementia.